Project Summary The goal of this core is to systematically characterize the molecular identities of distinct neuronal populations within the cortex using a combination of connectomics and cutting edge seqFISH methods to multiplex RNA detection in single cells. The Cai lab has recently developed a technology using sequential hybridization and single molecule FISH to multiplex a large number of mRNA molecules directly in single cells in complex tissue samples. A collaborative team at Columbia, UC Berkeley and at Caltech will apply this technology to identify distinct cell types in the mouse brain in situ following in vivo live calcium imaging experiments as well as in vitro connectivity measurements.